BAW pneumatic actuator is divide into the duulle action type and single action type, two split cylinders, with large output torque, flexible and steaty action. The piston rod is coated with hard chrome and had a good wearability. There equip with the oil free iubricating ahaft and guide ring between the slide parts so sa to drop the friction factor and prolong the service life. With the oil free lubricating ahaft and quide ring between the slide parts so as to drp the friction factor and prolong the service life. U type curve characheristic output torgue of BAW pneumatic is more suitable for large bore ball valve and butterfly valve. MF series pneumatic actuator widely used kinds of Straight travel type control valve.